The Los Angeles-based real estate firm's semi-annual report, Global Market Rents, lists current occupancy costs for office space in the Midtown Manhattan market at $64.92 per sf compared to $64.63 six months ago.

Of the 155 world markets studied, only London's West End shows a rise in office rents. At $157.63 per sf, up from $156.89 in January, the West End is also the most expensive area covered in the study. New York comes in at number 10.

Not surprisingly, Silicon Valley rents headed directly south, dropping from $87.48 per sf to 68.90, putting it just ahead of Midtown and handing it the number-nine slot on the list. But CBRE expects rents to continue to slide for the rest of they year, casting doubts on Silicon Valley's remaining in the top 10 next time out.